Pet food composition containing semi-refined gelling agent

ABSTRACT

A pet food composition containing chunks and a clear gellified sauce or base, said composition being obtainable by: i) incorporating at least one semi-refined gelling agent and/or semi-refined gelling biopolymer blend, in a mixture comprising meat and meat by-products, said mixture being used for the manufacture of the chunks; ii) mixing the manufactured chunks with a sauce or base containing no gelling agent; and iii) treating the mixture under conditions to release the pure gelling agent molecules from the chunks into the sauce or base to gelify it and to achieve chunk structure.

FIELD OF THE INVENTION

[0001] The present invention relates to pet food products containingchunks and sauce or base, and especially “chunks in jelly” productshaving improved gel clearness, chunk rigidity and processability. Theinvention also relates to a process of producing such pet food products.

BACKGROUND OF THE INVENTION

[0002] Today, the petfood industry is using mainly the glucomannan orgalactomannan-kappa carrageenan mixed systems in the production ofproducts of type loaf, chunks in loaf and chunks in jelly. Typically,the jelly is made using semi refined carrageenan. The galactomannanfamily consists in guar gum, tara gum, carob gum (or locust bean gum)and cassia gum; the glucomannan consists in konjac mannan gum.

[0003] In production, the restructured meat chunks are mixed with a semirefined carrageenan liquid jelly (with other hydrocolloids and dryingredients) and go together into the can. After retorting the semirefined carrageenan makes the jelly of final product.

[0004] Because these products are using semi refined kappa carrageenanthe jelly is somehow “cloudy”. This cloudiness is due to the milderextraction procedure from algae which results in a carrageenancontaining fragments of algal cell wall cellulose: of about 8-15%cellulosic material in the final composition of a typical semi refinedcarrageenan. In fact, the cellulose somehow precipitates during theretorting step and subsequently promotes the cloudiness of final gel. Inreality, the meat just released from the chunks (containing some proteinstuffs) may also complex with carrageenan cellulose precipitate,increasing even more the presence of precipitate material in the jelly.

[0005] The use of refined gelling agents, and particularly refined kappacarrageenan would improve the clearness of the final gel, but its use isquite limited in petfood industries due to high price, and semi refinedmaterial is largely used due to his low price.

[0006] Also, the chunk structure is achieved during the cooking andretorting steps mainly through animal or vegetable protein coagulation.Thus, the quality of the obtained chunks is highly dependant on thequality of the protein raw material. This is critical because of thevariability of the supplier sources and because of the market crisis(e.g. BSE, GMO).

[0007] Therefore, the present invention aims to improve the chunkrigidity and the clearness, of gels and global product quality controlin petfood products, without using refined gelling agents and/orfunctional proteins.

SUMMARY OF THE INVENTION

[0008] Accordingly, in one aspect, this invention provides a pet foodcomposition containing chunks and a clear gellified sauce or base, saidcomposition being obtainable by:

[0009] i) incorporating at least one semi-refined gelling agent and/orsemi-refined gelling biopolymer blend in a mixture comprising meat andmeat by-products, said mixture being used for the manufacture of thechunks,

[0010] ii) mixing the manufactured chunks with a sauce or basecontaining no gelling agent and,

[0011] iii) treating the mixture under conditions to release the puregelling agent molecules from the chunks into the sauce or base togellify it and to achieve the chunk structure.

[0012] In a prefered embodiment, at least one oligosaccharide oroligosaccharide blend may be further incorporated in the mixturecomprising meat and meat by-products.

[0013] Also, the sauce or base may contain a thickening and/or astabilizing agent.

[0014] In fact, it has been surprisingly found that it was possible toprepare chunks in jelly products, using semi-refined gelling agentsand/or semi-refined gelling biopolymer blend, and have in the finalproduct a very clear gel. Indeed, during the manufacture of thecomposition, the cellulose material of semi refined gelling agents,especially carrageenan, precipitates during heat treatment (retorting)but is retained in the chunk structure which behaves like a filter andonly the gelling molecules are released to the sauce or base.

[0015] Furthermore, the presence of polysaccharide in the chunk stuctureprovides an additional firmness due to complex formation betweensulfates groups of carrageenanes and ionic groups of proteins andpossible covalent bonds formation between residual sugar from hydrolysisof gelling agent (i.e. galactose, mannose or others oligosaccaharides)during the heat treatments and proteins. This structuration process canbe reinforced by further addition of reducing oligosaccharides (e.g.xylose, galactose, glucose, . . . ).

[0016] This petfood composition has an improved gel clearness withoutthe need to use refined gelling agents and an improved chunk rigidityand global product quality without using functionnal proteins.

[0017] The use of semi-refined gelling agent in the meat mix can bedetected by qualitative analysis of the cellulose from gelling agentthat precipitates in the chunk structure.

[0018] In another aspect, the invention relates to a process forpreparing a pet food composition containing chunks and a clear sauce orbase, comprising:

[0019] i) preparing a meat mixture which comprises meat and meatby-products and at least one semi refined gelling agent and/orsemi-refined gelling biopolymer blend

[0020] ii) using the meat mixture to manufacte meat chunks,

[0021] iii) preparing a sauce or base without adding semi refinedgelling agent

[0022] iv) mixing the meat chunks with the sauce or base and fillinginto a container

[0023] v) heating the container and contents to sterilize the contents.

DETAILED DESCRIPTION OF THE INVENTION

[0024] In the present description, meat and meat by-products areunderstood to mean all the fleshy parts of slaughtered warm-bloodedanimals in the fresh state or preserved by an appropriate treatment andall the products and by-products arising from the processing of thebodies or body parts of warm-blooded animals. Meat is understood to meanin particular the meat from chickens, rabbits, bovines or ovines andoffal. Offal is understood to mean lung lobes as well as livers orkidneys. Meat by-products is understood to mean the meal obtained fromcarcasses of the above mentioned animals. In the present description,fish and fish by-products will be regarded as coming within thedefinition of meat and meat by-products. Fish and fish by-products areunderstood to mean fish or fish parts in the fresh state or preserved byan appropriate treatment, as well as the by-products of theirprocessing. Salmon or sardines can be used as fish and fish meal can beused as by-products.

[0025] Also, semi refined gelling agents are understood to mean gellingagents partially or non refined, i.e. containing pure gelling agentmolecules that promote a gel on the molecular basis of the transitionfrom the “solution” to the “gel” state: it must involve some form ofassociation of biopolymer/polyssacharide chains (junction zones) inorder to produce a gel network structure (V. J. Morris, 1998, Gelationof Polysacharides, In: Functional Properties of Food Macromolecules, edsS E Hill, D A Ledward & J R Mitchell, Aspen Publishers, pp. 143-226).Semi refined gelling agents are understood to mean gelling agentspartially or non refined such like carrageenan, alginate, agar-agar,gellan, pectin, xanthan or association of those, among others.Typically, some gums that do not gelify alone when in mixture with othergums, due to synergistic interactions, present gelling properties (e.g.xanthan gun/glucomannan or galactomannan, etc) and may also be used assemi-refined gelling biopolymer blend.

[0026] Also, oligosaccharides are understood to mean either hydrolysisproducts from polysaccharides or added monosaccharides to react withprotein.

[0027] In the present description, all the percentages are by weightunless otherwise indicated.

[0028] According to a first aspect, the invention relates to a petfoodcomposition containing chunks and a clear gellified sauce or base, saidcomposition being obtainable by:

[0029] i) incorporating at least one semi-refined gelling agent and/orsemi-refined gelling biopolymer blend in a mixture comprising meat andmeat by-products, said mixture being used for the manufacture of thechunks,

[0030] ii) mixing the manufactured chunks with a sauce or basecontaining no gelling agent and,

[0031] iii) treating the mixture under conditions to release the puregelling agent molecules from the chunks into the sauce or base togellify it and to achieve chunk structure.

[0032] The semi refined gelling agent according to the present inventionmay be carrageenan (in particular kappa carrageenan), alginate,agar-agar, gellan, pectin, xanthan or association of those, amongothers. The semi-refined gelling biopolymer blend may be in the form ofmixture of gums which present gelling properties (e.g. xanthangum/glucomannan or galactomannan, etc).

[0033] The semi refined gelling agent or biopolymer blend may be presentin an amount of up to 10% by weight, based upon the total weight.

[0034] The presence of polysaccharide in the chunk stucture provides anadditional firmness due to complex formation between sulfates groups ofcarrageenanes and ionic groups of proteins and possible covalent bondsformation between residual sugar from hydrolysis of gelling agent (i.e.galactose, mannose or others oligosaccaharides) during heat treatment.

[0035] This structuration process can be reinforced by further additionof reducing oligosaccharides. Accordingly, in a prefered embodiment, atleast one oligosaccharide or oligosaccharide blend may be furtherincorporated in the mixture comprising meat and meatby-products. Theoligosaccharide may be xylose, galactose, glucose, fructose, mannose,saccharose or other reducing pentose or hexose or association of those,for example. Preferably, the oligosaccharide may be added in an amountof 0 to 20% by weight, based upon the total weight.

[0036] Preferably, the chunks of the composition according to theinvention contain less than 3% of particles having sizes of less than 4mm. It is clearly understood that, depending on whether the compositionis intended for cats or for dogs, the size of the chunks will bedifferent. For dogs, 50 to 60% of the chunks will not pass through ascreen with a mesh opening of 16 mm. For cats, on the other hand, only 5to 15% of the chunks will not pass through a screen with a mesh openingof 14 mm, 45 to 65% of the chunks having a size of between 8 and 14 mm.

[0037] In the composition, the chunks may be present in a proportion ofbetween 20 and 70%, the remainder being the sauce or the base. In thecase of a composition with sauce, the chunks can be present in aproportion of 40 to 60% whereas, with a composition with base, thechunks can be present in a proportion of 10 to 50%.

[0038] The pet food may be produced as is conventional. Apart from thegelling agent according to the present invention, the pet food mayinclude any one or more of a starch source, a protein source and lipidsource.

[0039] Suitable starch sources are, for example, grains and legumes suchas corn, rice, wheat, barley, oats, soy, and mixtures of these. Suitableprotein sources may be selected from any suitable animal or vegetableprotein source; for example meat and meal, poultry meal, fish meal, soyprotein concentrates, milk proteins, gluten, and the like. For elderlyanimals, it is preferred for the protein source to contain a highquality protein. Suitable lipid sources include meats, animal fats andvegetable fats.

[0040] The choice of the starch, protein and lipid sources will belargely determined by the nutritional needs of the animal, palatabilityconsiderations, and the type of product produced. For elderly pets, thepet food preferably contains proportionally less fat than pet foods foryounger pets. Further, the starch sources may include one or more ofrice, barley, wheat and corn.

[0041] Further, various other ingredients, for example, sugar, salt,spices, seasonings, vitamins, minerals, flavouring agents, fats and thelike may also be incorporated into the pet food as desired.

[0042] In a preferred embodiment, the chunks are prepared from a mixturecontaining 58 to 68% of meat and meat by-products, between 16 and 25% ofcereals, between 2 and 5% of vegetable protein extracts and up to 10% ofsemi refined gelling agent, and 5 to 14% of water. The meats and meatby-products preferably comprise a minimum of 10% of pig or beef liverand from 0 to 5% of powdered pig or beef plasma and the cereals arepresent in a proportion of at least 10%, the said cereals being wheat,maize or rice flours, which makes it possible to ensure that the chunkat the cutting off has a sufficient texture and to avoid the productionof fines and of tears. The chunks can additionally contain up to 3% ofdyes, vitamins and inorganic salts.

[0043] The powdered plasma can advantageously be substituted by at least2% of vegetable protein extracts which play the same role as the plasma.Furthermore, the present invention provides the possibility to replacetotally the animal or vegetal functional proteins (i.e. plasma, soya, .. . )

[0044] The chunks present in the composition can also be prepared from amixture additionally containing between 0 and 5% of vegetable proteinextract. Vegetable protein extract may be any product, of plant origin,the proteins of which have been concentrated by an appropriatetreatment, which contain at least 50% of crude proteins with respect tothe dry matter and which may have been restructured. The proteins usedare, for example, wheat or maize gluten or soya isolate.

[0045] In the mixture for preparing the chunks, the water content can beadjusted to between 0 and 15% according to the meat and cereal contents,in order to obtain a final moisture level of the chunks of preferablybetween 50 and 60% and more preferably between 52 and 58%, in order toensure a correct content of the emulsion in the manufacturing process.

[0046] Before mixing the meat and meat by-products, a size reduction ofthe said meats may be carried out in order to arrive at sizes of theorder of 12 mm. The meats (and optionally also the fish) are then mixedwith the other ingredients (optionally also the vegetable proteinextracts) of the chunk composition until homogenized, in order to obtainan elastic paste. Emulsification may then be carried out and theemulsified paste may then be pumped, with or without deaeration, to acontinuous shaping system which makes it possible to extrude puddings.The pudding paste thus obtained may be cooked by any continuous cookingsystem (for example, hot air, steam, hot air and steam or microwavesystem) in order to obtain a core temperature of between 80 and 95° C.The puddings are thus congealed by coagulation and can be sliced at theoutlet of the cooking device. The cooked coagulated paste is thencontinuously cut at the outlet of the cooking system into congulatedpieces with a length of 40 to 400 mm. The elongated pieces are thenhardened by cooling to a temperature of between 10 and 40° C.: thecooling is preferably carried out with water by spraying or immersion inorder to prevent the chunks from sticking to one another. It finallyremains to cube the cooled pieces. In order to do this, use is made of acuber known in the state of the art, such as the Urschel cuber.

[0047] According to the present invention, the viscosity of the meatmixture and the quality of the chunk cutting (i.e. less fines formation,better shape finition) are improved by the presence of the semi-refinedgelling agent and/or added oligosaccharides, even in the absence ofvegetable or animal functional protein.

[0048] The chunks thus obtained are mixed in a way known per se with thesauce or the base. Sauce is understood to mean a mixture containing upto 98% of water, the remainder being one or more thickeners, such asgums, dyes and flavouring agents. Base is understood to mean a mixturebased on 60 to 80% of water and 20 to 40% of finely ground meats, theremainder being thickeners, dyes and aromas.

[0049] The sauce or base according to the present invention does notcontain any gelling agent that promote a gel network as previouslydefined. Preferably, it contains a thickening and/or a stabilizingagent, suitable gums are locust bean gum, guar gum, cassia gum, carobgum and Konjac gum for example.

[0050] The pet foods are then filled into cans or other containers, thecontainers sealed, and the mixture is heat treated under conditions torelease the pure gelling agent molecules from the chunks into the sauceor base to gellify it. Preferably, the product is retorted in the normalmanner, e.g. the composition is finally sterilized conventionally at atemperature of between 120 and 135° C. for 20 to 100 min. Suitableequipment is commercially available.

[0051] The following examples are given by way of illustration only andin no way should be construed as limiting the subject matter of thepresent application. All percentages are given by weight unlessotherwise indicated.

EXAMPLES Examples 1 to 5

[0052] The gelling system used is composed of semi refined kappacarrageenan/semi refined carob gum/potassium chloride. The carob gum canbe replaced by other galactomannans like tara gum or cassia gum andglucomannans like konjac gum.

[0053] The viscosity of the jelly can be adjusted using guar gum inorder to proceed to filling cans either one step or two step filling.

Example 1

[0054] Jelly Semi refined carob gum   0.5% Potassium chloride   0.15%Liquid caramel   0.3% Flavor system   0.5% Water  97.35% Chunk Semirefined kappa carrageenan  1-1.5% Animal meats 78.5-79% Meat meals   10% Plasma powder   1.5% Flavor system     3% Salt   1.5% Colorant    1% Water     3%

Example 2

[0055] Jelly Cassia gum  0.5% Guar gum 0.25% Potassium chloride 0.15%Liquid caramel  0.3% Flavor system  0.5% Water 97.1% Chunk Recipe as inexample 1

Example 3

[0056] Jelly Konjac gum  0.5% Potassium chloride  0.15% Liquid caramel 0.3% Flavor system  0.5% Water 97.35% Chunk Recipe as in example 1

Example 4 Cat Composition “Chunks in a Jelly”

[0057] Jelly Semi refined carob gum   0.5% Potassium chloride   0.15%Liquid caramel   0.3% Flavor system   0.5% Water  97.35% Chunk Semirefined kappa carrageenan  1-1.5% Animal meats 78.5-79% Meat meals   10% Xylose   1.5% Flavor system     3% Salt   1.5% Colorant     1%Water     3%

Example 5 Cat Composition “Chunks in a Jelly”

[0058] Jelly Semi refined carob gum   0.5% Potassium chloride   0.15%Liquid caramel   0.3% Flavor system   0.5% Water  97.35% Chunk Semirefined kappa carrageenan  1-1.5% Animal meats 78.5-79% Meat meals    9% Galactose   2.0% Plasma powder   0.5% Flavor system     3% Salt  1.5% Colorant     1% Water     3%

Example 6 Cat Composition “Chunks in a Sauce”

[0059] A mixture is prepared from 73% of animal meats, 16% of wheatflour, 2% of powdered beef plasma, 6.8% of water, 2.2% of dyes and 1% ofsemi refined iota/kappa carrageenan, 1% xylose, vitamins and inorganicsalts. This mixture is emulsified at 12° C. and extruded in the form ofa pudding paste. This pudding paste is cooked at a temperature of 90°C., and pieces with a length of 80 mm are cut. They are cooled to 30° C.and cut in order to obtain chunks. 45% of these chunks are mixed with55% of sauce prepared from 98% of water, 1% of dye and 1% of guar gum.Tinplate cans are filled and sterilized.

Example 7 Cat Composition “Chunks in a Sauce”

[0060] A mixture is prepared from 73% of animal meats, 16% of wheatflour, 2% of powdered beef plasma, 6.8% of water, 2.2% of dyes and 1% ofsemi refined iota/kappa carrageenan, vitamins and inorganic salts. Thismixture is emulsified at 12° C. and extruded in the form of a puddingpaste. This pudding paste is cooked at a temperature of 90° C., andpieces with a length of 80 mm are cut. They are cooled to 30° C. and cutin the cuber in order to obtain chunks. 45% of these chunks are mixedwith 55% of sauce prepared from 98% of water, 1% of dye and 1% of guargum. Tinplate cans are filled and sterilized.

Example 8 Cat Composition “Chunks in a Base”

[0061] A mixture is prepared from 56% of animal meats, 16% of wheatflour, 2% of plasma, 10.8% of water and 2.2% of dyes, 1% of semi refinedkappa carrageenan, 3% glucose and vitamins and inorganic salts. Thepreparation is then carried out as in Example 6, in order to obtainchunks. 30% of these chunks (having a water content of 58%) isincorporated in a base prepared from 23% of poultry carcass, 1% of guargum, 1% of dye and aroma and 75% of water. Tinplate cans are then filledand sterilized.

Example 9 Cat Composition “Chunks in a Base”

[0062] A mixture is prepared from 56% of animal meats, 13% of fish, 16%of wheat flour, 2% of plasma, 10.8% of water and 2.2% of dyes, 1% ofsemi refined kappa carrageenan and vitamins and inorganic salts. Thepreparation is then carried out as in Example 6, in order to obtainchunks. 30% of these chunks (having a water content of 58%) isincorporated in a base prepared from 23% of poultry carcass, 1% of guargum, 1% of dye and aroma and 75% of water. Tinplate cans are then filledand sterilized.

Example 10 Dog Food Composition

[0063] 69% of animal meats is mixed with 20% of wheat flour, 1% ofpowdered beef plasma, 7.8% of water and 2.2% of dyes, 1% semi refinedkappa carrageenan, and vitamins and inorganic salts. This mixture isemulsified at 12° C. and extruded in the form of a pudding paste. Thispudding paste is cooked at a temperature of 90°, and pieces with alength of 80 mm are cut. They are cooled and cut in order to obtainchunks. 50% of these chunks are mixed with 50% of sauce prepared from98% of water, 1% of dye and 1% of guar gum. Tinplate cans are filled andsterilized.

Example 11 Qualitative Analysis of the Cellulose from Kappa Carrageenanin the Chunks

[0064] The use of semi refined kappa carrageenan in the meat mix can bechecked by qualitative analysis of the cellulose from kappa-carrageenanthat precipitates in the chunk structure. The methodology used is thefollowing:

[0065] separation by sieving of chunks from hot liquid jelly

[0066] extraction from the chunks the acid insoluble matter (cellulosefibers):

[0067] 200 g of product+200 ml concentrated sulfuric acid+600 mldesionized water,

[0068] stirring and heating 100° C. during 6 hours

[0069] stirring during one night

[0070] strirring and heating 100° C. during 1 hour

[0071] flitration

[0072] rinsing with 2 liters of desionized water

[0073] drying 2 hours 102° C.

[0074] removing of fat in Buchi extraction station with petroleumbenzine 2 hours

[0075] drying 2 hours 102° C.

[0076] powder

[0077] qualitative analysis by RMN of the presence or not of cellulosefrom semi refined kappa carrageenan. (Glyn O. Phillips, 1996, Gums andStabilisers for the Food Industry, 8, pp 403).

1. A pet food composition containing chunks and a clear gellified sauceor base, said composition being obtainable by: i) incorporating at leastone semi-refined gelling agent and/or semi-refined gelling biopolymerblend in a mixture comprising meat and meat by-products, said mixturebeing used for the manufacture of the chunks, ii) mixing themanufactured chunks with a sauce or base containing no gelling agentand, iii) treating the mixture under conditions to release the puregelling agent molecules from the chunks into the sauce or base togellify it and to achieve chunk structure.
 2. A pet food compositionaccording to claim 1 wherein the semi refined gelling agent iscarrageenan, alginate, agar-agar, gellan, pectin, xanthan or associationof those.
 3. A pet food composition according to claim 1, wherein thesemi refined gelling biopolymer blend is in the form of a mixture ofgums which present gelling properties, such as xanthan gum/glucomannanor galactomannan.
 4. A pet food composition according to one of claims 1to 3 wherein the semi refined gelling agent or gelling biopolymer blendis incorporated in an amount up to 10% by weight, based upon totalweight.
 5. A pet food composition according to one of claims 1 to 4,wherein at least one oligosaccharide or oligosaccharide blend is furtherincorporated in the mixture comprising meat and meat by-products.
 6. Apet food composition according to claim 5, wherein the oligosaccharideis xylose, galactose, glucose, fructose, mannose, saccharose or otherreducing pentose or hexose or association of those.
 7. A pet foodcomposition according to one of claims 1 to 6, wherein the sauce or basecomprises a thickening and/or a stabilizing agent.
 8. A pet foodcomposition according to one of claims 1 to 7, wherein chunks arecombined with the sauce in an amount of from 40% to 60%, by weight,based upon the total weight or wherein the chunks are combined with thebase in an amount of 10% to 50%, by weight, based upon the total weight.9. A process for preparing a pet food composition containing chunks anda clear sauce or base, comprising: i) preparing a meat mixture whichcomprises meat and meat by-products and at least one semi refinedgelling agent and/or semi refined gelling biopolymer blend, ii) usingthe meat mixture to manufacture meat chunks, iii) preparing a sauce orbase without adding semi refined gelling agent iv) mixing the meatchunks with the sauce or base and filling into a container v) heatingthe container and contents to sterilize the contents.
 10. A processaccording to claim 9, wherein at least one oligosaccharide oroligosaccharide blend is further incorporated in the meat mixture.
 14. Aproduct according to any one of claims 11 to 13 comprising thesemi-refined gelling agent or biopolymer blend in amount up to 10% byweight based upon total weight of the product.
 15. A product accordingto any one of claims 11 to 14 wherein the gelling agent is kappacarrageenan.